US9066773B2 - Rotary drive cutter for dentistry - Google Patents

Rotary drive cutter for dentistry Download PDF

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Publication number
US9066773B2
US9066773B2 US12/601,222 US60122208A US9066773B2 US 9066773 B2 US9066773 B2 US 9066773B2 US 60122208 A US60122208 A US 60122208A US 9066773 B2 US9066773 B2 US 9066773B2
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United States
Prior art keywords
shank
neck part
straight portion
cutting
base
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US12/601,222
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US20100173263A1 (en
Inventor
Satoshi Tetsuka
Nobuhiro Muraoka
Kazuaki KATOH
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Mani Inc
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Mani Inc
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Assigned to MANI, INC. reassignment MANI, INC. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: KATOH, KAZUAKI, MURAOKA, NOBUHIRO, TETSUKA, SATOSHI
Publication of US20100173263A1 publication Critical patent/US20100173263A1/en
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    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
    • A61C1/00—Dental machines for boring or cutting ; General features of dental machines or apparatus, e.g. hand-piece design
    • A61C1/02—Dental machines for boring or cutting ; General features of dental machines or apparatus, e.g. hand-piece design characterised by the drive of the dental tools
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
    • A61C3/00—Dental tools or instruments
    • A61C3/02—Tooth drilling or cutting instruments; Instruments acting like a sandblast machine
    • A61C5/023—
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
    • A61C5/00—Filling or capping teeth
    • A61C5/40—Implements for surgical treatment of the roots or nerves of the teeth; Nerve needles; Methods or instruments for medication of the roots
    • A61C5/42—Files for root canals; Handgrips or guiding means therefor

Definitions

  • the present invention relates to a dental rotary drive cutting tool such as a peeso reamer or a gates drill.
  • a dental rotary drive cutting tool such as a peeso reamer or a gates drill is used for the purpose of cutting such layer.
  • the peeso reamer and the gates drill only differ in shape of cutting edge formed at the tip, and have the same basic structure and function of cutting tooth dentin.
  • FIG. 5 is a diagram showing the structure of the peeso reamer disclosed in Patent Document 1
  • FIG. 6 is an enlarged sectional view cut along a line I-I of FIG. 5 .
  • a cutting portion 1 is formed along a predetermined length of a peeso reamer A from one end, and a shank 2 having a predetermined length is formed on the other end.
  • a neck part 3 constitutes the part between the cutting portion 1 and the shank 2 .
  • each of the cutting edges 1 a has a preset angle of torsion, and the external shape of the side surface is straight.
  • the peeso reamer A is rotated and operated by gripping a rotary drive device chuck such as a hand piece or the like, which is omitted from the drawings.
  • a rotary drive device chuck such as a hand piece or the like, which is omitted from the drawings.
  • the shank 2 has a straight whirl-stop 2 a corresponding to the chuck.
  • the neck part 3 is formed straight having a smaller diameter than outer diameters of the cutting portion 1 and the shank 2 , and respective connecting parts on either end with the cutting portion 1 and the shank 2 are formed in an R shape having a predetermined curvature radius.
  • the aforementioned structure is also for the gates drill.
  • the corresponding portion to the cutting portion 1 shown in FIG. 5 also has multiple cutting edges with a preset angle of torsion, the angle of torsion (angle between cutting edge and axial center) is large, and the structure in which the external form of the cutting portion formed in a spherical shape differs from that of the peeso reamer.
  • the peeso reamer A formed as described above is made of austenitic stainless steel.
  • Austenitic stainless steel is excellent in that it does not rust, but it cannot be hardened by quenching. Therefore, in Patent Document 1, austenitic stainless steel wire rod is subjected to a cold wiredrawing process so that the crystal structure is pulled along the line length and made thinner into a fiber structure, work hardened, and then used. Making it into such a fibrous structure allows setting a predetermined hardness of Hv 500 or greater, for example.
  • the composition by axially pulling the composition into fibers through cold wire-drawing, improvement in bending strength and exhibition of uniform strength without any fluctuation across the entire length is possible.
  • the aforementioned wire rod is cut to a length corresponding to the target peeso reamer A, making materials, and the materials are then machined to make the peeso reamer A.
  • the material obtained by cold wire-drawing austenitic stainless steel has a concentric hardness distribution. In other words, hardness at the surface is highest, and gradually decreases toward the center. Thus, it is hard at the cutting portion 1 and the shank 2 and softer at the neck part 3 .
  • the neck part 3 is narrower and softer than other parts, it bends easily along the root canal curve and rotates in the bent state.
  • the cutting edges la cut dentin on the inner wall of the root canal according to this rotation to perform a specific treatment. Since the peeso reamer A rotates in a bent state, a single rotation applies a single-lap bending force on the neck part 3 . Through repetitive use, it is bent repeatedly for the number of rotations, and thus the hardness gradually increases and bending fatigue is accumulated. Therefore, the peeso reamer A eventually breaks.
  • the neck part 3 is narrow, the breaking place may be limited to the neck part 3 without breaking at the cutting portion 1 or the shank 2 .
  • the peeso reamer A breaks at a position near the shank 2 of the neck part 3 , the broken end of the neck part 3 protrudes from the root canal. Therefore, the peeso reamer A may be extracted from the root canal by pinching and counter-rotating the protruded portion with pliers or the like. However, if it breaks near the cutting portion 1 , the broken portion enters the root canal and cannot be pinched.
  • a peeso reamer that has a tapered neck part 5 as shown in FIG. 7 is proposed.
  • This neck part 5 is wider on the cutting portion 1 side and narrower on the shank 2 side.
  • the narrowest portion 5 a is near the shank 2 .
  • stress when the peeso reamer A is rotated converges at the narrow portion 5 a , and when bending fatigue accumulates and it breaks off, the reamer may be easily extracted.
  • the conventional technology mentioned above has a problem that it breaks off easier than when the neck part 5 is not tapered.
  • the present invention is devised through consideration of these problems.
  • An objective thereof is to provide a dental rotary drive cutting tool that can limit breaking locations to the shank side and is difficult to break off.
  • a dental rotary drive cutting tool of the present invention reaching the above-given purpose is characterized in that it includes a cutting portion formed on the tip side, a shank formed in a base, and a neck formed between the cutting portion and the shank.
  • the neck comprises a tapered portion, which is wider on the tip side and narrower on the base side, and a straight portion, which has a constant thickness with the same diameter as that of the end of the tapered portion on the base side.
  • a connecting part, which gradually becomes thicker towards the shank, may be formed between the straight portion and the shank, or a connecting part, which gradually becomes thicker towards the cutting portion, may be provided between the cutting portion and the tapered portion.
  • the material may have a structure made of austenite stainless steel pulled into fibers.
  • the dental rotary drive cutting tool according to the present invention is pressed into a curved tooth root canal, rotates in a curved state, and cuts the inner wall of the root canal. Since it rotates in a curved state, the tapered portion is repeatedly bent, and hardness is thus increased, and bending fatigue is accumulated; however, all of this occurs across the entire straight portion. Therefore, beneficial effects such as limiting breaking location to the narrowest tapered portion, and increasing life span until breakage, namely making it difficult to break are achieved.
  • FIG. 1 is a diagram showing principal parts of a peeso reamer of the present invention
  • FIG. 2 is a diagram showing principal parts of a gates drill of the present invention
  • FIG. 3 is a diagram describing conditions for a break test
  • FIG. 4 is a chart giving results of the break test
  • FIG. 5 is a diagram showing the structure of the peeso reamer disclosed in Patent Document 1;
  • FIG. 6 is an enlarged sectional view cut along a line I-I of FIG. 5 ;
  • FIG. 7 is a diagram of a conventional peeso reamer having a tapered neck part.
  • FIG. 1 is a diagram showing principal parts of a peeso reamer 10 of the present invention.
  • This peeso reamer 10 includes a straight cutting portion 11 at the tip, and a shank 12 at the base.
  • the cutting portion 11 includes multiple cutting edges 11 a .
  • the shank 12 includes a whirl-stop like the whirl-stop 2 a of the conventional example.
  • this neck part 13 While there is a neck part 13 between the cutting portion 11 and the shank 12 , this neck part 13 has a tapered portion 13 a which is wider on the cutting portion side and is narrower on the shank 12 side.
  • This structure is the same as that in the conventional example described using FIG. 7 .
  • the case of the present invention is characteristic in that a straight portion 13 b is formed in the narrowest tapered area.
  • a connecting part 13 c between the straight portion 13 b and the shank 12 is formed in an R shape having a predetermined curvature radius.
  • a similar connecting part 13 d is formed between the cutting portion 11 and the tapered portion 13 a.
  • the overall length of the peeso reamer 10 is 32 mm
  • length of the cutting portion 11 is 8.5 mm
  • length of the shank 12 is 13 mm
  • length of the whirl-stop is 2.7 mm
  • length L 1 of the neck part 13 is 10.5 mm
  • Diameter D 1 of the shank 12 is 2.35 mm
  • length L 2 of the tapered portion 13 a is 6.45 to 7.2 mm, where there are six kinds of diameters ranging in width from 0.55 to 1.05 mm in accordance with the diameter of the cutting portion 11 , difference between the long diameter and short diameter is 0.04 mm, and length L 3 of the straight portion 13 b is 1.0 mm.
  • length L 4 of the connecting part 13 c is 2.8 mm and length L 5 of the connecting part 13 d is from 0.5 to 1.25 mm.
  • the narrowest portion 5 a is limited to one axial point.
  • the neck part 5 rotates in a curved state, and increase in hardness and accumulation of bending fatigue at this time concentrates at this narrowest point. Thus, it is easily broken at an early stage.
  • the length of the straight portion 13 b or the narrowest portion is 1.0 mm.
  • FIG. 2 is a diagram showing principal parts of a gates drill 20 according to the present invention.
  • This gates drill 20 includes a bulb-shaped cutting portion 21 at the tip, and a shank 22 at the base.
  • the cutting portion includes multiple cutting edges 21 a .
  • the angle of torsion of the cutting edges 21 a (angle between cutting edge and axial center) is larger than that of the cutting edges 11 a of the peeso reamer 10 .
  • the shank 22 includes a whirl-stop like the whirl-stop 2 a of the conventional example.
  • this neck part 23 is between the cutting portion 21 and the shank 22 , this neck part 23 having a tapered portion 23 a which is wider on the cutting portion 21 side and is narrower on the shank 22 side is the same as in the conventional example described using FIG. 7 .
  • a straight portion 23 b is formed in the narrowest tapered area.
  • a connecting part 23 c between the straight portion 23 b and the shank 22 is formed in an R shape having a predetermined curvature radius.
  • Length L 3 of the straight portion 23 b is 1 mm, which is the same as in the case of the peeso reamer 10 of FIG. 1 .
  • FIG. 3 is a diagram describing conditions for the break test.
  • the shank 22 of the gates drill 20 is grasped and kept level, a load is applied to a predetermined location from the tip, and is rotated in a state vertically lowered to only a predetermined distance.
  • the length of the peeso reamer and the gates drill is 32 mm, and diameters indicate those of the cutting portion 21 , which are: #1 is ⁇ 0.5 mm, #2 is ⁇ 90.7 mm, and #3 is ⁇ 0.9 mm.
  • Distance W from the tip to the location in which a load is applied is 4.5 mm for all types of the peeso reamer.
  • distances W are: #1 is 1.5 mm, #2 is 1.7 mm, and #3 is 1.9 mm.
  • Distance (pressed amount) S that it is lowered vertically is 2 mm for all.
  • FIG. 4 is the chart giving results of the break test. Numbers written in each column are rotations per minute at the time of breakage. Those on the upper side are for the present invention, and those on the lower side are for the conventional tool. The narrowest edge #1 of the gates drill of the present invention did not break even when the rotations per minute reached one hundred thousand times. Moreover, for #1, #2 and #3, the life span of the structure according to the present invention including the straight portions is increased. Particularly, the narrowest #1 had a remarkable tendency for a longer life span.
  • Diameters #1, #2, and #3 of five of each of the conventional tool, which does not include the straight portions 13 b and 23 b , and the present invention formed with the straight portions 13 b and 23 b are tested under the above-given conditions. With both the peeso reamer and the gates drill, #1, #2, and #3 all give the same or slightly higher results than the conventional tool. Torque for #1 of the peeso reamer is 476 gcm for the conventional tool and 493 gcm for the present invention, and torque for #1 of the gates drill is 244 gcm for the conventional tool and 250 gcm for the present invention, where the torque for the present invention is 1.03 times greater than that of the conventional tool.

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  • Health & Medical Sciences (AREA)
  • Oral & Maxillofacial Surgery (AREA)
  • Dentistry (AREA)
  • Epidemiology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Engineering & Computer Science (AREA)
  • Biomedical Technology (AREA)
  • Neurology (AREA)
  • Neurosurgery (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Surgery (AREA)
  • Dental Tools And Instruments Or Auxiliary Dental Instruments (AREA)
  • Surgical Instruments (AREA)
US12/601,222 2007-05-30 2008-05-21 Rotary drive cutter for dentistry Active US9066773B2 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP2007-142725 2007-05-30
JP2007142725A JP5233016B2 (ja) 2007-05-30 2007-05-30 歯科用の回転駆動切削具
PCT/JP2008/059318 WO2008146670A1 (ja) 2007-05-30 2008-05-21 歯科用の回転駆動切削具

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US20100173263A1 US20100173263A1 (en) 2010-07-08
US9066773B2 true US9066773B2 (en) 2015-06-30

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US12/601,222 Active US9066773B2 (en) 2007-05-30 2008-05-21 Rotary drive cutter for dentistry

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US (1) US9066773B2 (es)
EP (1) EP2151212B1 (es)
JP (1) JP5233016B2 (es)
KR (1) KR101473506B1 (es)
CN (1) CN101677838B (es)
BR (1) BRPI0812019B8 (es)
CA (1) CA2686549C (es)
ES (1) ES2730698T3 (es)
MX (1) MX2009012805A (es)
RU (1) RU2464951C2 (es)
WO (1) WO2008146670A1 (es)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11504211B2 (en) 2018-04-10 2022-11-22 Mani, Inc. Dental file
US11771522B2 (en) 2019-08-22 2023-10-03 Mani, Inc. Dental root canal treatment instrument
US11890155B2 (en) 2018-08-29 2024-02-06 Mani, Inc. Dental file

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101083528B1 (ko) * 2009-04-28 2011-11-16 이준호 지대치 형성용 역경사 프렙 버
KR101717084B1 (ko) * 2015-08-31 2017-03-20 주식회사 제노스 치아 임플란트 식립용 드릴링 드라이버
ES2677998B1 (es) * 2017-02-07 2019-05-20 Vogul S L U Destornillador para implantes dentales
KR102049703B1 (ko) * 2019-10-28 2019-11-28 장천석 파절 가능 영역을 개선한 치아 신경 치료용 엔도파일
US20230008344A1 (en) * 2021-07-07 2023-01-12 Todd C. SNYDER Dental bur

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US4345899A (en) * 1979-07-12 1982-08-24 Vlock D G Dental twist drill
JPH07299622A (ja) 1994-04-27 1995-11-14 Mekuto:Kk ドリル
US5664914A (en) 1994-04-27 1997-09-09 Kabushiki Kaisha Mekuto Drill
US5816807A (en) 1995-02-02 1998-10-06 Kabushiki Kaisha Matsutani Seisakusho Rotary drilling instrument
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JPH11290344A (ja) 1998-04-13 1999-10-26 Keiji Murase 根管口明示用リ−マ−及びファイル
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US20020119418A1 (en) * 2001-02-28 2002-08-29 Mani, Inc. Dental reamer
US20030159544A1 (en) 2002-02-28 2003-08-28 Bernhard Moser Method for the production of a tool, in particular a drill or milling cutter
US20070082318A1 (en) * 2003-04-24 2007-04-12 Olivier Breguet Instrument for drilling radicular channels

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US4345899A (en) * 1979-07-12 1982-08-24 Vlock D G Dental twist drill
JPH07299622A (ja) 1994-04-27 1995-11-14 Mekuto:Kk ドリル
US5664914A (en) 1994-04-27 1997-09-09 Kabushiki Kaisha Mekuto Drill
US5836764A (en) * 1994-04-28 1998-11-17 Buchanan; Leonard Stephen Endodontic treatment system
JP3375771B2 (ja) 1995-02-02 2003-02-10 マニー株式会社 ピーソーリーマ又はゲーツドリル
US5816807A (en) 1995-02-02 1998-10-06 Kabushiki Kaisha Matsutani Seisakusho Rotary drilling instrument
JPH11290344A (ja) 1998-04-13 1999-10-26 Keiji Murase 根管口明示用リ−マ−及びファイル
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US20010004518A1 (en) 1999-12-17 2001-06-21 Mani, Inc. Dental root canal therapeutic instrument
US20020119418A1 (en) * 2001-02-28 2002-08-29 Mani, Inc. Dental reamer
US20030159544A1 (en) 2002-02-28 2003-08-28 Bernhard Moser Method for the production of a tool, in particular a drill or milling cutter
JP2003275928A (ja) 2002-02-28 2003-09-30 Hawera Probst Gmbh 工具及びその製造方法
US20070082318A1 (en) * 2003-04-24 2007-04-12 Olivier Breguet Instrument for drilling radicular channels

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11504211B2 (en) 2018-04-10 2022-11-22 Mani, Inc. Dental file
US11890155B2 (en) 2018-08-29 2024-02-06 Mani, Inc. Dental file
US11771522B2 (en) 2019-08-22 2023-10-03 Mani, Inc. Dental root canal treatment instrument

Also Published As

Publication number Publication date
JP2008295603A (ja) 2008-12-11
CN101677838A (zh) 2010-03-24
BRPI0812019B1 (pt) 2020-03-31
EP2151212A1 (en) 2010-02-10
EP2151212B1 (en) 2019-04-10
BRPI0812019A2 (pt) 2014-11-18
KR20100022024A (ko) 2010-02-26
CA2686549C (en) 2015-04-07
MX2009012805A (es) 2009-12-10
US20100173263A1 (en) 2010-07-08
ES2730698T3 (es) 2019-11-12
CN101677838B (zh) 2013-04-17
KR101473506B1 (ko) 2014-12-16
RU2464951C2 (ru) 2012-10-27
BRPI0812019B8 (pt) 2021-06-22
JP5233016B2 (ja) 2013-07-10
RU2009149213A (ru) 2011-07-10
EP2151212A4 (en) 2014-03-26
CA2686549A1 (en) 2008-12-04
WO2008146670A1 (ja) 2008-12-04

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